US7528519B2 - Permanent magnet rotary motor - Google Patents

Permanent magnet rotary motor Download PDF

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Publication number
US7528519B2
US7528519B2 US11/532,932 US53293206A US7528519B2 US 7528519 B2 US7528519 B2 US 7528519B2 US 53293206 A US53293206 A US 53293206A US 7528519 B2 US7528519 B2 US 7528519B2
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magnetic pole
angle
type connecting
connecting portion
constituent
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US20070063610A1 (en
Inventor
Toshihito Miyashita
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Sanyo Denki Co Ltd
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Sanyo Denki Co Ltd
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/12—Stationary parts of the magnetic circuit
    • H02K1/14—Stator cores with salient poles
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/12—Stationary parts of the magnetic circuit
    • H02K1/14—Stator cores with salient poles
    • H02K1/146—Stator cores with salient poles consisting of a generally annular yoke with salient poles
    • H02K1/148—Sectional cores
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/12—Stationary parts of the magnetic circuit
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/12—Stationary parts of the magnetic circuit
    • H02K1/18—Means for mounting or fastening magnetic stationary parts on to, or to, the stator structures
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
    • H02K29/03—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K21/00—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
    • H02K21/02—Details
    • H02K21/021—Means for mechanical adjustment of the excitation flux
    • H02K21/022—Means for mechanical adjustment of the excitation flux by modifying the relative position between field and armature, e.g. between rotor and stator

Definitions

  • the present invention relates to a permanent magnet rotary motor.
  • stator core there is known such a stator core that has an annular yoke and magnetic pole constituent member disposed inside the yoke.
  • the magnetic pole constituent member comprises a plurality of pole columns, magnetic pole surface constituent sections formed on the pole column and connecting portions connecting two adjacent sections among the magnetic pole surface constituent sections.
  • Japanese Patent Publication Application No. 2002-199630 discloses a permanent magnet rotary motor in which pole columns are disposed at unequal intervals to vary the dimensions between adjacent pole columns to reduce the cogging torque.
  • Japanese Patent Publication Application No. 2002-10539 discloses a permanent magnet rotary motor in which a plurality of holes are formed discontinuously along an axial direction in its connecting portions and are opened both inwardly in a radial direction and toward a slot between two adjacent pole columns. The plurality of holes are formed in order to prevent leakage of magnetic flux among the magnetic poles.
  • An object of the present invention is to provide a permanent magnet rotary motor in which the cogging torque can be reduced without largely reducing the torque.
  • Another object of the present invention is to provide a permanent magnet rotary motor in which the inductance can be balanced in its exciting winding sections.
  • Still another object of the present invention is to provide a permanent magnet rotary motor, which can be easily manufactured and in which the cogging torque can be reduced.
  • a permanent magnet rotary motor of the present invention comprises a rotor, a stator core and N (N is an even number of 4 or more) exciting winding sections.
  • the rotor includes a rotor core fixed to a rotary shaft and a plurality of permanent-magnet magnetic pole sections composed of permanent magnets attached to the rotor core.
  • the stator core includes an annular yoke, N pole columns disposed inside the annular yoke at intervals in a circumferential direction of the yoke with one end of the pole column being connected to the yoke and the other end thereof being positioned on an inner side than the one end in a radial direction of the yoke.
  • the stator core also includes N magnetic pole surface constituent sections respectively formed on the other end of the N pole columns, each having on its inner side a magnetic pole surface facing the rotor, and N connecting portions connecting two adjacent sections among the magnetic pole surface constituent sections.
  • Each of the N connecting portions is formed with one or more through-holes penetrating the connecting portion in the radial direction.
  • the N exciting winding sections are mounted onto the N pole columns of the stator core respectively.
  • the N connecting portions include N/2 first type connecting portions and N/2 second type connecting portions, and the first and second type connecting portions are alternately disposed in a circumferential direction of the rotor.
  • first type connecting portion When an angle formed between two virtual lines respectively connecting a center of the rotary shaft and both ends, mutually opposed in the circumferential direction, of the first type connecting portion is defined as a first angle ⁇ 1 and an angle formed between two virtual lines respectively connecting the center of the rotary shaft and both ends, mutually opposed in the circumferential direction, of the second type connecting portion is defined as a second angle ⁇ 2 , a relationship between the first angle ⁇ 1 and the second angle ⁇ 2 is ⁇ 1 > ⁇ 2 .
  • the first type connecting portion is formed with a through-hole, which extends from a center position of the first type connecting portion as viewed in an axial direction of the rotary shaft toward both sides in the axial direction.
  • the second type connecting portion is formed with a through-hole, which extends from a center position of the second type connecting portion as viewed in the axial direction toward both sides in the axial direction.
  • the length of the through-hole formed in the first type connecting portion is longer than the length of the through-hole formed in the second type connecting portion in the circumferential direction.
  • the length of the through-hole formed in the first type connecting portion is shorter than the length of the through-hole formed in the second type connecting portion in the axial direction.
  • an inner circumferential portion of the stator core may be constituted by three parts disposed along the axial direction of the rotary shaft: (1) a part where no through-holes are formed in all of the connecting portions disposed in the circumferential direction; (2) a part where through-holes are alternately formed in the connecting portions disposed in the circumferential direction; and (3) a part where through-holes are formed in all of the connection portions disposed in the circumferential direction.
  • the through-holes are formed only in the second-type connecting portions, the length of which in the circumferential direction is shorter than that of the first type connection portions.
  • the first angle ⁇ 1 of the first type connecting portion is appropriately larger than the second angle ⁇ 2 of the second type connecting portion so that the formulae (A) to (C) are satisfied.
  • the leakage magnetic flux is reduced to prevent the torque from decreasing.
  • the cogging torque can be reduced without largely reducing the torque.
  • the inductance in the exciting winding sections can be balanced by alternately disposing in the circumferential direction longer through-holes and shorter through-holes, the shorter through-hole having a length shorter than the longer through-hole in the axial direction.
  • the first type connecting portion may be formed with a first through-hole, which extends from one end of the first type connecting portion in the axial direction of the rotary shaft toward the other end thereof, and a second through-hole, which extends from the other end of the first type connecting portion in the axial direction toward the one end.
  • the second type connecting portion may be formed with a third through-hole, which extends from one end of the second type connecting portion in the axial direction toward the other end thereof, and a fourth through-hole, which extends from the other end of the second type connecting portion in the axial direction toward the one end.
  • the length, in the circumferential direction, of the first and second through-holes formed in the first type connecting portion is longer than the length, in the circumferential direction, of the third and fourth through-holes formed in the second type connecting portion.
  • the length, in the axial direction, of the first and second through-holes formed in the first type connecting portion is shorter than the length, in the axial direction, of the third and fourth through-holes formed in the second type connecting portion.
  • the first through-hole and the second through-hole may be equal to each other in the axial direction, and the third through-hole and the fourth through-hole may be equal to each other in the axial direction.
  • the first type connecting portion can be formed with a through-hole, which extends from one end of the first type connecting portion in the axial direction of the rotary shaft toward the other end thereof; and the second type connecting portion can be formed with a through-hole, which extends from one end of the second type connecting portion in the axial direction toward the other end thereof.
  • the length, in the circumferential direction, of the through-hole formed in the first type connecting portion is longer than the length, in the circumferential direction, of the through-hole formed in the second type connecting portion.
  • the length, in the axial direction, of the through-hole formed in the first type connecting portion is shorter than the length, in the axial direction, of the through-hole formed in the second type connecting portion. In this manner also, the cogging torque can be reduced without largely reducing the torque. Also, the inductance in the exciting winding sections can be balanced.
  • a value ( ⁇ 2 / ⁇ 1 ) obtained by dividing the second angle ⁇ 2 by the first angle ⁇ 1 is preferably set to a range of 0.25 ⁇ 2 / ⁇ 1 ⁇ 0.35.
  • the angle range, measured in the circumferential direction, of the through-hole formed in the first type connecting portion may be equal to the first angle ⁇ 1 ; and the angle range, measured in the circumferential direction, of the through-hole formed in the second type connecting portion may be equal to the second angle ⁇ 2 .
  • the stator core of the permanent magnet rotary motor according to the present invention includes a yoke and a magnetic pole constituent member disposed inside the yoke.
  • the magnetic pole constituent member may be composed of first-kind, second-kind, and third-kind magnetic pole constituent steel-plate layers which are overlaid on one another.
  • Each of the layers is made of a magnetic steel-plate, and includes a pole column constituent portion partially constituting the pole column and a magnetic pole surface constituent portion partially constituting the magnetic pole surface constituent section.
  • Two different intermediate portions are formed between two adjacent portions among the magnetic pole surface constituent portions included in each of the first-kind to third-kind magnetic pole constituent steel-plate layers; i.e., first intermediate portions and second intermediate portions each have a different angle range measured in the circumferential direction.
  • first intermediate portion an angle formed between two virtual lines respectively connecting a center of the rotor and two ends, mutually opposed in the circumferential direction, of the two adjacent magnetic pole surface constituent portions is a first angle ⁇ 1 .
  • second intermediate portion an angle formed between two virtual lines respectively connecting the center of the rotor and two ends, mutually opposed in the circumferential direction, of the two adjacent magnetic pole surface constituent portions is a second angle ⁇ 2 , which is smaller than the first angle ⁇ 1 .
  • Both of the first and second intermediate portions of the first-kind magnetic pole constituent steel-plate layer are opened to partially form the through-holes.
  • the first intermediate portions of the second-kind magnetic pole constituent steel-plate layer partially constitute the connecting portions, and the second intermediate portions thereof are opened to partially form the through-holes. Both of the first intermediate portions and the second intermediate portions of the third-kind magnetic pole constituent steel-plate layer partially form the connecting portions.
  • the magnetic pole constituent member is composed of the third-kind magnetic pole constituent steel-plate layer, the second-kind magnetic pole constituent steel-plate layer, the first-kind magnetic pole constituent steel-plate layer, the second-kind magnetic pole constituent steel-plate layer and the third-kind magnetic pole constituent steel-plate layer which are overlaid on one another in this order so that the ratio for the number of layers is 1:2:4:2:1.
  • the through-hole which extends from a center position of the first type connecting portion, and the through-hole, which extends from a center position of the second type connecting portion, are formed.
  • stator core in which the length of the through-hole formed in the first type connecting portion is shorter than the length of the through-hole formed in the second type connecting portion, by simply overlaying in the axial direction of the rotor three kinds of magnetic pole constituent steel-plate layers each made of a magnetic steel-plate.
  • the magnetic pole constituent member may be composed of the first-kind magnetic pole constituent steel-plate layer, the second-kind magnetic pole constituent steel-plate layer, the third-kind magnetic pole constituent steel-plate layer, the second-kind magnetic pole constituent steel-plate layer and the first-kind magnetic pole constituent steel-plate layer which are overlaid on one another in this order so that the ratio for the number of layers is 2:2:2:2:2.
  • the first and second through-holes are formed in both ends of the first type connecting portion
  • the third and fourth through-holes are formed in both ends of the second type connecting portion.
  • stator core in which the length of the first and second through-holes is shorter than the length of the third and fourth through-holes, by simply overlaying in the axial direction of the rotor three kinds of magnetic pole constituent steel-plate layers each made of a magnetic steel-plate.
  • the magnetic pole constituent member may be composed of the third-kind magnetic pole constituent steel-plate layer, the second-kind magnetic pole constituent steel-plate layer and the first-kind magnetic pole constituent steel-plate layer which are overlaid on one another in this order so that the ratio for the number of layers is 2:4:4.
  • the inner circumferential portion of the stator core may be constituted by three parts disposed along the axial direction of the rotary shaft: (1) a part where no through-holes are formed in all of the connecting portions disposed in the circumferential direction; (2) a part where through-holes are alternately formed in the connecting portions disposed in the circumferential direction; and (3) a part where through-holes are formed in all of the connection portions disposed in the circumferential direction.
  • the cogging torque can be reduced without largely reducing the torque.
  • the inductance in the exciting winding sections can be balanced by alternately disposing in the circumferential direction longer through-holes and shorter through-holes, the shorter through-hole having a length shorter than the longer through-hole in the axial direction.
  • FIG. 1 is a schematic diagram of a permanent magnet rotary motor in accordance with a first embodiment of the present invention.
  • FIG. 2 is a perspective view of a stator core used in the permanent magnet rotary motor shown in FIG. 1 .
  • FIG. 3 is a partial illustration of a stator core used in the permanent magnet rotary motor shown in FIG. 1 as viewed from an inner side (rotor side) thereof.
  • FIG. 4 is a plan view of a first-kind magnetic pole constituent steel-plate layer of the stator core used in the permanent magnet rotary motor shown in FIG. 1 .
  • FIG. 5 is a plan view of a second-kind magnetic pole constituent steel-plate layer of the stator core used in the permanent magnet rotary motor shown in FIG. 1 .
  • FIG. 6 is a plan view of a third-kind magnetic pole constituent steel-plate layer of the stator core used in the permanent magnet rotary motor shown in FIG. 1 .
  • FIG. 7 is a perspective view of a stator core used in a permanent magnet rotary motor in accordance with a second embodiment of the present invention.
  • FIG. 8 is a partial illustration of the stator core used in the permanent magnet rotary motor shown in FIG. 7 as viewed from an inner side (rotor side) thereof.
  • FIG. 9 is a perspective view of a stator core used in a permanent magnet rotary motor in accordance with a third embodiment of the present invention.
  • FIG. 10 is a partial illustration of the stator core used in the permanent magnet rotary motor shown in FIG. 9 as viewed from an inner side (rotor side) thereof.
  • FIG. 11 is a partial illustration of a stator core used in a permanent magnet rotary motor in accordance with a varied or modified embodiment of the present invention.
  • FIG. 12 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in the permanent magnet rotary motor of the first embodiment.
  • FIG. 13 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in the permanent magnet rotary motor of the second embodiment.
  • FIG. 14 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in the permanent magnet rotary motor of the third embodiment.
  • FIG. 15 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in the permanent magnet rotary motor of FIG. 11 .
  • FIG. 16 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in a permanent magnet rotary motor of a comparative example 1 in which a magnetic pole constituent member is formed by overlaying only the first-kind magnetic pole constituent steel-plate layers shown in FIG. 4 .
  • FIG. 17 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in a permanent magnet rotary motor of a comparative example 2 in which a magnetic pole constituent member is formed by overlaying only the second-kind magnetic pole constituent steel-plate layers shown in FIG. 5 .
  • FIG. 18 is a chart showing a relationship between the rotation angle of the rotor and the cogging torque in a permanent magnet rotary motor of a comparative example 3 in which a magnetic pole constituent member is formed by overlaying only the third-kind magnetic pole constituent steel-plate layers shown in FIG. 6 .
  • FIG. 1 is a schematic diagram of a permanent magnet rotary motor according to a first embodiment of the present invention.
  • the permanent magnet rotary motor of the first embodiment comprises a rotor 1 and a stator 3 as shown in FIG. 1 .
  • the rotor 1 includes a rotor core 5 fixed to a rotary shaft 2 and eight permanent-magnet magnetic pole sections composed of plate-like permanent magnets 7 , which are disposed on an outer surface of the rotor core 5 at equal intervals in a circumferential direction of the rotor core 5 .
  • one permanent magnet 7 constitutes one permanent-magnet magnetic pole section.
  • the rotor core 5 is composed of a plurality of electromagnetic steel-plates which are overlaid on one another.
  • the eight permanent magnets 7 are arranged on the surface of the rotor core 5 so that N-pole and S-pole appear alternately along the circumferential direction.
  • the stator 3 includes a stator core 9 and exciting winding sections 11 .
  • the exciting winding sections 11 are indicated with a broken line in FIG. 1 .
  • the stator core 9 includes an annular yoke 13 and a magnetic pole constituent member 15 arranged inside the annular yoke 13 as shown in FIGS. 1 to 3 .
  • FIG. 2 is a perspective view of the stator core 9 and FIG. 3 is a partial illustration of the stator core 9 as viewed from the inside thereof (rotor side).
  • the pole columns 17 are arranged inside the yoke 13 at intervals in the circumferential direction, and each of the pole columns 17 has one end, which is connected to the yoke 13 , and the other end, which is positioned at an inner side than the one end in a radial direction of the yoke. In this embodiment, each of the pole columns 17 has a projection 17 a on the one end.
  • the projection 17 a is fitted into a recess 13 a formed in the inner periphery of the yoke 13 , thereby connecting the pole column 17 to the yoke 13 .
  • Each of the magnetic pole surface constituent sections 19 has on its inner side a magnetic pole surface 19 a , which is formed on the other end of the pole column 17 and faces the rotor 1 .
  • the N (6) connecting portions 21 A, 21 B respectively connect two adjacent sections among the magnetic pole surface constituent sections 19 , and include N/2 (3) first type connecting portions 21 A and N/2 (3) second type connecting portions 21 B.
  • the first type connection portions 21 A and the second type connecting portions 21 B are alternately disposed in a circumferential direction of the rotor.
  • first type connecting portion 21 A When an angle formed between two virtual lines respectively connecting a center C of the rotary shaft 2 of the rotor 1 and both ends, mutually opposed in the circumferential direction, of the first type connecting portion 21 A is defined as a first angle ⁇ 1 and an angle formed between two virtual lines respectively connecting the center C of the rotary shaft 2 of the rotor 1 and both ends, mutually opposed in the circumferential direction, of the second type connecting portion 21 B is defined as a second angle ⁇ 2 , a relationship between the first angle ⁇ 1 and the second angle ⁇ 2 is ⁇ 1 > ⁇ 2 .
  • a value obtained by dividing the second angle ⁇ 2 by the first angle ⁇ 1 ( ⁇ 2 / ⁇ 1 ) is within a range of 0.25 ⁇ 2 / ⁇ 1 ⁇ 0.35.
  • the first type connecting portion 21 A is formed with a through-hole H 1 , which extends from a center position of the first type connecting portion 21 A as viewed in an axial direction of the rotary shaft 2 toward both sides in the axial direction (the axial direction of the rotary shaft 2 indicated with an arrow AD) as shown in FIG. 3 in detail.
  • the second type connecting portion 21 B is formed with a through-hole H 2 , which extends from a center position of the second type connecting portion 21 B as viewed in the axial direction toward both sides in the axial direction (indicated with arrow AD).
  • an angle range measured in the circumferential direction (in a circumferential direction of the rotary shaft 2 indicated with an arrow PD) of the through-hole H 1 formed in the first type connecting portion 21 A is equal to the first angle ⁇ 1 .
  • An angle range measured in the circumferential direction of the through-hole H 2 formed in the second type connecting portion 21 B is equal to the second angle ⁇ 2 . Therefore, the length, in the circumferential direction, of the through-hole H 1 formed in the first type connecting portion 21 A is longer than the length, in the circumferential direction, of the through-hole H 2 formed in the second type connecting portion 21 B.
  • the length L 1 , in the axial direction, of the through-hole H 1 formed in the first type connecting portion 21 A is shorter than the length L 2 , in the axial direction, of the through-hole H 2 formed in the second type connecting portion 21 B.
  • the ratio of the length L 1 of the through-hole H 1 with respect to the length L 2 of the through-hole H 2 is 1:2.
  • the magnetic pole constituent member 15 is composed of a plurality of magnetic steel-plates, which are overlaid on one another.
  • the magnetic pole constituent member 15 is composed of a combination of a first-kind magnetic pole constituent steel-plate layer 27 shown in FIG. 4 , a second-kind magnetic pole constituent steel-plate layer 29 shown in FIG. 5 and a third-kind magnetic pole constituent steel-plate layer 31 shown in FIG. 6 , which are overlaid on one another.
  • the first-kind magnetic pole constituent steel-plate layer 27 is composed of six divided magnetic steel-plates 27 A to 27 F as shown in FIG. 4 .
  • Each of the magnetic steel-plates includes a pole column constituent portion 27 a that constitutes the pole column 21 and a magnetic pole surface constituent portion 27 b that constitutes the magnetic pole surface constituent section 19 .
  • Two kinds of intermediate portions are formed between two ends, adjacent to each other in the circumferential direction, of the magnetic pole surface constituent portions 27 b . That is, the intermediate portions are a first intermediate portion 27 c in which the first angle ⁇ 1 is formed between two virtual lines respectively connecting two ends of the first intermediate portion 27 c and the center C of the rotor, and a second intermediate portions 27 d in which the second angle ⁇ 2 , smaller than the first angle ⁇ 1 , is formed between two virtual lines respectively connecting the two ends of the second intermediate portion 27 d and the center C of the rotor.
  • the first intermediate portions 27 c and the second intermediate portions 27 d are disposed alternately in the circumferential direction. Both of the first intermediate portions 27 c and the second intermediate portions 27 d are opened to partially form the through-holes H 1 and H 2
  • the second-kind magnetic pole constituent steel-plate layer 29 is composed of three divided magnetic steel-plates 29 A to 29 C.
  • Each of the magnetic steel-plates includes two pole column constituent portions 29 a that constitute the pole column 21 and two magnetic pole surface constituent portions 29 b that constitute the magnetic pole surface constituent section 19 .
  • Two kinds of intermediate portions are formed between two ends, adjacent to each other in the circumferential direction, of the magnetic pole surface constituent portions 29 b .
  • the intermediate portions are a first intermediate portion 29 c in which the first angle ⁇ 1 is formed between two virtual lines respectively connecting two ends of the first intermediate portions 29 c and the center C of the rotor, and a second intermediate portions 29 d in which the second angle ⁇ 2 , smaller than the first angle ⁇ 1 , is formed between two virtual lines respectively connecting the two ends of the second intermediate portions 29 d and the center C of the rotor.
  • the first intermediate portion 29 c and the second intermediate portion 29 d are alternately disposed in the circumferential direction.
  • the first intermediate portion 29 c is formed of a connecting-portion constituent portion 29 e that partially constitutes the first type connecting portion 21 A.
  • the second intermediate portion 29 d is opened to partially form the through-hole H 2 .
  • the third-kind magnetic pole constituent steel-plate layer 31 is composed of a magnetic steel-plate and includes six pole column constituent portions 31 a that constitute the pole columns 21 , and six magnetic pole surface constituent portions 31 b that constitute the magnetic pole surface constituent sections 19 . Two kinds of intermediate portions are formed between two ends, adjacent to each other in the circumferential direction, the magnetic pole surface constituent portions 31 b .
  • the intermediate portions are a first intermediate portion 31 c in which the first angle ⁇ 1 is formed between two virtual lines respectively connecting two ends of the intermediate portions 31 c and the center C of the rotor, and a second intermediate portions 31 d in which the second angle ⁇ 2 , smaller than the first angle ⁇ 1 , is formed between two virtual lines respectively connecting the two ends of the intermediate portion 31 d and the center C of the rotor.
  • the first intermediate portion 31 c and the second intermediate portion 31 d are alternately disposed in the circumferential direction.
  • the first intermediate portion 31 c is formed of a connecting-portion constituent portion 31 e that partially constitutes the first type connecting portion 21 A
  • the second intermediate portion 31 d is formed of a connecting-portion constituent portion 31 f that partially constitutes the second type connecting portion 21 B.
  • the magnetic pole constituent member 15 is composed of the third-kind magnetic pole constituent steel-plate layer 31 , the second-kind magnetic pole constituent steel-plate layers 29 , the first-kind magnetic pole constituent steel-plate layers 27 , the second-kind magnetic pole constituent steel-plate layers 29 and the third-kind magnetic pole constituent steel-plate layer 31 , which are overlaid on one another in this order so that the ratio for the number of plates is 1:2:4:2:1.
  • the inner circumferential portion of the stator core (constituted by the magnetic pole surface constituent section 19 , and the first and second type connecting portions 21 A, 21 B) are constituted by three parts disposed along the axial direction of the rotary shaft: (1) a part constituted by the third-kind magnetic pole constituent steel-plate layer 31 where no through-holes are formed in all of the connecting portions disposed in the circumferential direction; (2) a part constituted by the second-kind magnetic pole constituent steel-plate layer 29 where through-holes are alternately formed in the connecting portions disposed in the circumferential direction; and (3) a part constituted by the first-kind magnetic pole constituent steel-plate layer 27 where through-holes are formed in all of the connection portions disposed in the circumferential direction.
  • FIG. 7 is a perspective view of a stator core 109 used in a permanent magnet rotary motor in accordance with a second embodiment of the present invention.
  • FIG. 8 is a partial illustration of the stator core 109 used in the permanent magnet rotary motor shown in FIG. 7 as viewed from an inner side (rotor side) thereof.
  • the permanent magnet rotary motor in accordance with the second embodiment has the same structure as that of the permanent magnet rotary motor in accordance with the first embodiment except for the structure of the connecting portion of the stator core.
  • a first type connecting portion 121 A is formed with a first through-hole H 11 , which extends from one end toward the other end of the first type connecting portion 121 A in an axial direction (arrow AD) of the rotary shaft 2 , and a second through-hole H 12 , which extends from the other end toward the one end of the first type connecting portion 121 A in the axial direction.
  • the second type connecting portion 121 B is formed with a third through-hole H 13 , which extends from one end toward the other end of the second type connecting portion 121 B in the axial direction, and a fourth through-hole H 14 , which extends from the other end toward the one end of the second type connecting portion 121 B in the axial direction.
  • a length L 11 , in the axial direction, of the first through-hole H 11 is equal to a length L 12 , in the axial direction, of the second through-hole H 12 .
  • a length L 13 , in the axial direction, of the third through-hole H 13 is equal to a length L 14 , in the axial direction, of the fourth through-hole H 14 .
  • the lengths L 11 , L 12 , in the axial direction, of the first and second through-holes H 11 and H 12 formed in the first type connecting portion 121 A is respectively shorter than the length L 13 , L 14 , in the axial direction, of the third and fourth through-holes H 13 and H 14 formed in the second type connecting portion.
  • the ratio between the lengths L 11 , L 12 of the through-holes H 11 and H 12 and the lengths L 13 , L 14 of the through-holes H 13 and H 14 is 1:2.
  • the magnetic pole constituent member 115 is composed of the first-kind magnetic pole constituent steel-plate layers 27 shown in FIG. 4 , the second-kind magnetic pole constituent steel-plate layers 29 shown in FIG. 5 , the third-kind magnetic pole constituent steel-plate layers 31 shown in FIG. 6 , the second-kind magnetic pole constituent steel-plate layers 29 and the first-kind magnetic pole constituent steel-plate layers 27 , which are overlaid in this order so that the ratio for the number of plates is 2:2:2:2:2.
  • FIG. 9 is a perspective view of a stator core 209 used in a permanent magnet rotary motor in accordance with a third embodiment of the present invention.
  • FIG. 10 is a partial illustration of the stator core 209 used in the permanent magnet rotary motor shown in FIG. 9 as viewed from an inner side (rotor side) thereof.
  • the permanent magnet rotary motor in accordance with the third embodiment has the same structure as that of the permanent magnet rotary motor in accordance with the first embodiment except for the structure of the connecting portion of the stator core.
  • the first type connecting portion 221 A is formed with a through-hole H 21 , which extends from one end toward the other end of the first type connecting portion 221 A in the axial direction of the rotary shaft 2 (arrow AD).
  • the second type connecting portion 221 B is formed with a through-hole H 22 , which extends from one end toward the other end of the second type connecting portion 221 B in the axial direction.
  • the length L 21 , in the axial direction, of the through-hole H 21 formed in the first type connecting portion 221 A is shorter than the length L 22 , in the axial direction, of the through-hole H 22 formed in the second type connecting portion 221 B.
  • the ratio between the length L 21 of the through-hole H 21 and the length L 22 of the through-hole H 22 is 1:2.
  • the magnetic pole constituent member 215 is constructed of the third-kind magnetic pole constituent steel-plate layers 31 shown in FIG. 6 , the second-kind magnetic pole constituent steel-plate layers 29 shown in FIG. 5 and the first-kind magnetic pole constituent steel-plate layers 27 shown in FIG. 4 which are overlaid in this order so that the ratio for the number of plates is 2:4:4.
  • FIG. 11 is a partial illustration of a stator core 309 used in a permanent magnet rotary motor in accordance with a varied or modified embodiment of the present invention, as viewed from an inner side (rotor side) thereof.
  • the permanent magnet rotary motor in accordance with the third embodiment has the same structure as that of the permanent magnet rotary motor in accordance with the first embodiment except for the structure of the connecting portion of the stator core.
  • the first type connecting portion 321 A is formed with a through-hole H 31 , which extends from one end toward the other end of the first type connecting portion 321 A in the axial direction of the rotary shaft 2 (arrow AD).
  • the second type connecting portion 321 B is formed with a through-hole H 32 , which extends from one end toward the other end of the second type connecting portion 321 B in the axial direction.
  • the length L 31 , in the axial direction, of the through-hole H 31 formed in the first type connecting portion 321 A is shorter than the length L 32 , in the axial direction, of the through-hole H 32 formed in the second type connecting portion 321 B.
  • the ratio between the length L 31 of the through-hole H 31 and the length L 32 of the through-hole H 32 is 1:2.
  • FIGS. 12 to 14 respectively show the relationships between the rotation angle and the cogging torque of the rotor in the respective permanent magnet rotary motors according to the first to third embodiments.
  • FIG. 15 shows a relationship between the rotation angle and the cogging torque of the rotor of a permanent magnet rotary motor of a varied or modified embodiment of the present invention shown in FIG. 11 .
  • FIG. 16 shows a relationship between the rotation angle and the cogging torque of the rotor of a permanent magnet rotary motor of a comparative example 1, in which the magnetic pole constituent member is formed by overlaying only the first-kind magnetic pole constituent steel-plate layers 27 shown in FIG.
  • FIG. 17 shows a relationship between the rotation angle and the cogging torque of the rotor of a permanent magnet rotary motor of a comparative example 2, in which the magnetic pole constituent member is formed by overlaying only the second-kind magnetic pole constituent steel-plate layers 29 shown in FIG. 5 (in this case, the connecting portions are alternately opened).
  • FIG. 18 shows a relationship between the rotation angle and the cogging torque of the rotor of a permanent magnet rotary motor of a comparative example 3, in which the magnetic pole constituent member was formed by overlaying only the second-kind magnetic pole constituent steel-plate layers 29 shown in FIG. 6 (in this case, the connecting portions are all closed).
  • the cogging torque can be reduced in the permanent magnet rotary motors according to the first to third embodiments, compared to the permanent magnet rotary motors of the comparative examples 1 to 3, in which the magnetic pole constituent member is composed by overlaying only one of the first-kind, second-kind, and third-kind magnetic pole constituent steel-plate layers.
  • a permanent magnet rotary motor comprising:
  • a rotor including a rotary shaft, a rotor core fixed to the rotary shaft, and a plurality of permanent-magnet magnetic pole sections composed of a plurality of permanent magnets attached to the rotor core;
  • a stator core including an annular yoke, N (N is an even number of 4 or more) pole columns disposed inside the annular yoke at intervals in a circumferential direction of the yoke with one end of the pole column being connected to the yoke and the other end thereof being positioned on an inner side than the one end in a radial direction of the yoke, N magnetic pole surface constituent sections respectively formed on the other end of the N pole columns, each having on its inner side a magnetic pole surface facing the rotor, and N connecting portions connecting two adjacent sections among the magnetic pole surface constituent sections, and formed with one or more through-holes penetrating therethrough in the radial direction; and
  • N exciting winding sections respectively mounted onto N pole columns of the stator core
  • the N connecting portions including N/2 first type connecting portions and N/2 second type connecting portions, the first and second type connecting portions being alternately disposed in a circumferential direction of the rotor,
  • first type connecting portion when an angle formed between two virtual lines respectively connecting a center of the rotary shaft and both ends, mutually opposed in the circumferential direction, of the first type connecting portion is defined as a first angle ⁇ 1 and an angle formed between two virtual lines respectively connecting the center of the rotary shaft and both ends, mutually opposed in the circumferential direction, of the second type connecting portion is defined as a second angle ⁇ 2 , a relationship between the first angle ⁇ 1 and the second angle ⁇ 2 is ⁇ 1 > ⁇ 2 ;
  • a through-hole is formed in the first type connecting portion, extending from one end of the first type connecting portion in the axial direction of the rotary shaft toward the other end thereof;
  • a through-hole is formed in the second type connecting portion, extending from the other end of the second type connecting portion in the axial direction toward the one end thereof;
  • each of the through-holes formed in the first and second type connecting portions extends a length equal to each other from the center position toward both sides in the axial direction.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Iron Core Of Rotating Electric Machines (AREA)
  • Permanent Magnet Type Synchronous Machine (AREA)
  • Permanent Field Magnets Of Synchronous Machinery (AREA)
  • Dc Machiner (AREA)
US11/532,932 2005-09-20 2006-09-19 Permanent magnet rotary motor Active 2027-11-09 US7528519B2 (en)

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JP2005-272564 2005-09-20
JP2005272564A JP4476202B2 (ja) 2005-09-20 2005-09-20 永久磁石型回転モータ

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US20070063610A1 US20070063610A1 (en) 2007-03-22
US7528519B2 true US7528519B2 (en) 2009-05-05

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EP (1) EP1770847A3 (ko)
JP (1) JP4476202B2 (ko)
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US20080191576A1 (en) * 2007-02-13 2008-08-14 Sanyo Denki Co., Ltd. Stator for motor
US20090072647A1 (en) * 2007-09-11 2009-03-19 Hitachi, Ltd. Electric Rotating Machine and Automobile Equipped with It
DE102010036926A1 (de) * 2010-08-10 2012-02-16 Dorin Iles Stator für eine elektrische Maschine und Verfahren zu dessen Herstellung
US20120098376A1 (en) * 2008-09-15 2012-04-26 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Wurzburg Permanent-magnet synchronous motor and electric power-assisted steering system
US20120256513A1 (en) * 2009-12-02 2012-10-11 Brose Fahrzeugteile Gmbh & Co Kg, Wurzburg Stator for an electric motor and method for the production thereof
US20140339947A1 (en) * 2013-05-16 2014-11-20 Lasko Holdings, Inc. Multi-Piece Stator For An Electric Motor
US20150229166A1 (en) * 2014-02-10 2015-08-13 Sanyo Denki Co., Ltd. Stator core and permanent magnet motor
US20210218293A1 (en) * 2018-06-07 2021-07-15 Moteurs Leroy-Somer Stator for a rotating electrical machine

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JP2009100531A (ja) * 2007-10-16 2009-05-07 Mabuchi Motor Co Ltd インナーロータブラシレスモータ及びその製造方法
DE202008017448U1 (de) * 2008-08-15 2009-10-01 Ina Drives & Mechatronics Gmbh & Co. Ohg Aktiveinheit einer elektrischen Maschine
DE102009001588A1 (de) * 2009-03-17 2010-09-23 Hilti Aktiengesellschaft Stator für eine elektrodynamische Maschine
US20110175482A1 (en) * 2010-01-20 2011-07-21 Savagian Peter J Optimized stator tooth tip for a motor with axially inserted stator windings
CN103683561A (zh) * 2012-09-07 2014-03-26 上海三菱电梯有限公司 旋转电机的定子
JP5932147B2 (ja) 2013-05-31 2016-06-08 三菱電機株式会社 多重多相巻線交流回転電機および電動パワーステアリング装置
CN103312058A (zh) * 2013-06-28 2013-09-18 浙江宇静电机有限公司 一种分体式电机定子铁芯
CN104348271B (zh) * 2013-08-09 2019-07-23 德昌电机(深圳)有限公司 单相无刷电机
CN104348268B (zh) * 2013-08-09 2019-07-23 德昌电机(深圳)有限公司 单相无刷电机
KR101554390B1 (ko) 2013-10-01 2015-09-18 재단법인 한국기계전기전자시험연구원 회전전기기계용 고정자 및 이를 구비하는 회전전기기계
CN104638784B (zh) * 2013-11-08 2017-06-20 珠海格力节能环保制冷技术研究中心有限公司 定子结构及电机
JP6188639B2 (ja) * 2014-06-13 2017-08-30 三菱電機株式会社 電動機
CN107078567B (zh) * 2014-11-05 2019-04-23 三菱电机株式会社 电枢的层叠铁芯和电枢
CN105449880A (zh) * 2015-10-20 2016-03-30 杭州桢正机器人科技有限公司 大直径电机定子结构及其安装方法
DE102016201967A1 (de) * 2016-02-10 2017-08-10 Robert Bosch Gmbh Stator für eine elektrische Maschine, insbesondere für einen Innenäulfer-Elektromotor
JP6900846B2 (ja) * 2017-09-05 2021-07-07 株式会社デンソー ステータコア
FR3087962B1 (fr) * 2018-10-29 2022-01-14 Circor Ind Moteur electrique a courant continu sans balai avec un couple de crantage reduit et son procede de fabrication
JP6676133B1 (ja) * 2018-11-26 2020-04-08 山洋電気株式会社 電機子モールド構造
GB2615358B (en) * 2022-02-07 2024-06-26 Hispeed Ltd Stator with asymmetric material bridges for an electric machine

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080191576A1 (en) * 2007-02-13 2008-08-14 Sanyo Denki Co., Ltd. Stator for motor
US7569965B2 (en) * 2007-02-13 2009-08-04 Sanyo Denki Co., Ltd. Stator for motor
US20090072647A1 (en) * 2007-09-11 2009-03-19 Hitachi, Ltd. Electric Rotating Machine and Automobile Equipped with It
US20120098376A1 (en) * 2008-09-15 2012-04-26 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Wurzburg Permanent-magnet synchronous motor and electric power-assisted steering system
US8614532B2 (en) * 2008-09-15 2013-12-24 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Wurzburg Permanent-magnet synchronous motor and electric power-assisted steering system
US20120256513A1 (en) * 2009-12-02 2012-10-11 Brose Fahrzeugteile Gmbh & Co Kg, Wurzburg Stator for an electric motor and method for the production thereof
DE102010036926A1 (de) * 2010-08-10 2012-02-16 Dorin Iles Stator für eine elektrische Maschine und Verfahren zu dessen Herstellung
US20140339947A1 (en) * 2013-05-16 2014-11-20 Lasko Holdings, Inc. Multi-Piece Stator For An Electric Motor
US20150229166A1 (en) * 2014-02-10 2015-08-13 Sanyo Denki Co., Ltd. Stator core and permanent magnet motor
US9698634B2 (en) * 2014-02-10 2017-07-04 Sanyo Denki Co., Ltd. Stator core and permanent magnet motor
US20210218293A1 (en) * 2018-06-07 2021-07-15 Moteurs Leroy-Somer Stator for a rotating electrical machine
US11949284B2 (en) * 2018-06-07 2024-04-02 Moteurs Leroy-Somer Stator for a rotating electrical machine

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EP1770847A2 (en) 2007-04-04
CN1937357A (zh) 2007-03-28
CN1937357B (zh) 2010-09-22
US20070063610A1 (en) 2007-03-22
KR20070032928A (ko) 2007-03-23
JP2007089271A (ja) 2007-04-05
JP4476202B2 (ja) 2010-06-09
EP1770847A3 (en) 2013-10-23
KR101116670B1 (ko) 2012-03-07

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